1. Field of the Invention
The invention relates to forming anastomoses between hollow anatomical bodies and also forming ports that pass into the interior or lumen of hollow bodies. More particularly, the invention relates to using magnetic force to form anastomoses and creating magnetic ports in vessels.
2. Description of Related Art
Despite the considerable advances that have been realized in cardiology and cardiovascular surgery, heart disease remains the leading cause of death throughout much of the world. Coronary artery disease, or arteriosclerosis, is the single leading cause of death in the United States today. As a result, those in the cardiovascular field continue to search, with varying degrees of success, for new and improved manners of treating cardiovascular disease.
Coronary artery disease is currently treated by interventional procedures such as percutaneous transluminal coronary angioplasty (PTCA), coronary stenting and atherectomy, as well as surgical procedures including coronary artery bypass grafting (CABG). The goal of these procedures is to reestablish or improve blood flow through occluded (or partially occluded) coronary arteries, and is accomplished, for example, by enlarging the blood flow lumen of the artery or forming a bypass that allows blood to circumvent the occlusion. What procedure(s) is used typically depends on the severity and location of the blockage. CABG is typically performed when interventional procedures have been unsuccessful or, for one reason or another, are not available options for a given patient. When successful, these procedures restore flow within the treated vessel(s) and feed blood to myocardial tissue that had previously been insufficiently perfused.
Another proposed treatment places the target vessel, e.g., a coronary artery, in direct fluid communication with a heart chamber containing blood, for example, the left ventricle. Blood flows from the ventricle into a conduit that is in fluid communication with the artery; as such, this treatment may be described as a ventricular bypass procedure. Benefits of this procedure include obviating the need to manipulate the aorta, for example, as is done when a side-biting clamp is used in a typical CABG procedure to create a proximal anastomosis between the bypass graft and the aorta.
The most challenging aspect of CABG (as well as many other procedures that requiring forming an anastomosis) is connecting the graft vessel to the target vessel in a secure, fluid-tight manner. This is conventionally done by hand using suture that is passed through the tissue of the two vessels to create a handsewn connection. The small diameter of coronary vessels (typically 1 mm to 4 mm) makes creating these handsewn anastomoses highly technical and time consuming. The difficulty in forming the sutured anastomosis is exacerbated when access to the target vessel is restricted or limited as compared to open-chest CABG, for example, as in minimally invasive or percutaneous procedures. A number of other medical procedures also require the attachment of hollow anatomical bodies (by sewing or otherwise) and therefore involve the same or similar considerations, for instance, treating peripheral vascular disease or injury and creating arteriovenous shunts.
Many various anastomotic couplings have been proposed in the art, although none has performed well enough to receive any significant level of acceptance in the field. Exemplary problems experienced by some of these couplers include damage to the graft or target vessel wall, for instance, due to piercing, penetrating or overly compressing the tissue, and failure to produce repeatable results. Additionally, producing an anastomotic coupler that creates and maintains a patent connection has been somewhat elusive and hard to achieve.
Accordingly, there is a need in the art for methods and devices for forming a reliable anastomosis between hollow bodies in a relatively quick, easy and repeatable manner.
According to one embodiment, a method for securing a magnetic anastomotic component to a hollow body is provided and includes steps of providing an anastomotic component capable of producing or being attracted by a magnetic field, the component having an opening, positioning a placement member in a first configuration within a lumen of a hollow body at a selected location, the placement member being capable of producing or being attracted by a magnetic field, and using magnetic attraction between the anastomotic component and the placement member to position the component at a selected location. The anastomotic component is secured to the hollow body, the placement member is changed from the first configuration to a second configuration and then removed from the lumen of the hollow body.
According to another embodiment, a method for securing a magnetic anastomotic to a blood vessel having a lumen includes steps of placing an anastomotic component having an opening adjacent a blood vessel having a lumen, the anastomotic component capable of producing or being attracted by a magnetic field, providing a plurality of separate attachment members each of which is configured to be engaged with the anastomotic component, and securing the anastomotic component to the blood vessel by using the separate attachment members.
According to another embodiment, a method for adhesively securing a magnetic anastomotic component to an end of a hollow body having a lumen is provided. This method includes steps of providing an anastomotic component capable of producing or being attracted by a magnetic field, the component having an opening adapted to be placed in communication with a lumen of a hollow body, applying adhesive to at least one of the anastomotic component and the hollow body adjacent an end of the hollow body, and using the adhesive to secure the anastomotic component to the hollow body adjacent the end of the hollow body.
According to yet another embodiment, a method for securing a magnetic anastomotic component to an end of a hollow body having a lumen is provided and includes steps of providing an anastomotic component including first and second portions, at least one of the first and second portions being capable of producing or being attracted by a magnetic field, positioning the first portion of the anastomotic component within a lumen of a hollow body, positioning the second portion of the anastomotic component at least partially around the exterior of the hollow body, and allowing the first and second portions to compress the tissue of the hollow body to secure the anastomotic component to the hollow body.
According to still another embodiment, a method for checking a seal between an anastomotic component and a blood vessel to which the anastomotic component is secured is provided. This method includes steps of providing an anastomotic component capable of producing or being attracted by a magnetic field, the anastomotic component having an opening, attaching the anastomotic component to a blood vessel in fluid communication with the lumen of the blood vessel, using a cover to block the opening in the anastomotic component, the cover being capable of producing or being attracted by a magnetic field, and using magnetic attraction to maintain a seal between the cover and the anastomotic component and prevent blood from exiting through the opening in the anastomotic component, whereby any blood that does leak may be attributed to leaking at the attachment between the anastomotic component and the hollow body.
According to yet another embodiment, a method for confirming the proper orientation of a magnetic anastomotic component is provided. This method includes steps of providing a delivery device supporting at least one anastomotic component having an opening, the anastomotic component being capable of producing a magnetic field, providing a fixture including at least one portion that is magnetized according to a selected polarity and movable to a location adjacent the anastomotic component, and using the fixture to determine whether the anastomotic component is oriented properly on the delivery device.
According to another embodiment, a magnetic anastomotic component is provided having a first portion with an opening adapted to be placed in communication with a lumen of a hollow body, and a second portion attached to the first portion and including an expandable tubular body configured to be attached to an end of the hollow body. The first and second portions are disposed generally transverse to each other and at least one of them is capable of producing or being attracted by a magnetic field.
According to another embodiment, a magnetic anastomotic component is provided and has an annular body and a plurality of separate attachment members each of which may be selectively engaged with the annular body to secure it to a hollow body. At least one of the annular body and the attachment members is capable of producing or being attracted to a magnetic field.
According to still another embodiment, a device for checking the seal between an anastomotic component and a hollow body to which it is secured is provided. The device includes an expandable structure with a substantially fluid-impervious surface and material capable of producing or being attracted by a magnetic field. The expandable structure may be magnetically attached to a magnetic or ferromagnetic anastomotic component secured to a hollow body by placing the fluid-impervious surface over the component to block flow. The expandable structure is expanded to break the magnetic attraction between the magnetic material and the component.